Radical resection of a primary unresectable duodenal cancer after chemotherapy using S-1 and cisplatin: report of a case

BACKGROUND: Therapeutic outcomes and prognosis of primary unresectable duodenal cancer remains unsatisfactory, because effective chemotherapy is not established. CASE PRESENTATION: A 71-year-old male diagnosed with unresectable duodenal carcinoma with distant lymph node metastases was judged inoperable (cT3N2M1 cStage in UICC(7th)). Duodenal obstruction developed due to tumor growth, and the patient underwent laparoscopic gastro-jejunostomy and then combined chemotherapy using S-1 and cisplatin. Abdominal CT revealed reduction of the tumor, and lymph node swelling almost disappeared after chemotherapy. He underwent subtotal stomach-preserving pancreaticoduodenectomy and lymph node dissection including the para-aortic region. The final stage was fT3N1M0, StageIIIA in UICC(7th). He developed pancreatic fistula (ISGPF grade B), which subsided, and he was discharged 29 days after operation. He underwent adjuvant chemotherapy using S-1 for 1 year, and he remains well without recurrence. CONCLUSIONS: S-1/cisplatin combination chemotherapy allowed R0 resection for advanced duodenal cancer.